JPH1144689A - Immune analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an immunity analyzer in which the capillary flow of a sample liquid in a coloring region is made uniform and whose detecting accuracy is enhanced by a method wherein a space is formed in a region at least in a part of the coloring region formed on a chromatography strip. SOLUTION: Spaces 9 are formed on the top surface and/or the bottom surface of a region at least in a part of a coloring region formed on a chromatography strip 1 in which a substrate 2 is pasted on the bottom surface and in which a protective laminate 3 is pasted on the surface. When a sample liquid which has a possibility of containing a detected substance is added to a sample addition region 5, the sample liquid is moved to a downstream direction by a capillary flow. The coloring region on the downstream of the sample addition region is a region which is colored during an analysis, and it contains a detecting region 6 which is used to detect the detected substance, in the sample liquid. In this manner, when the spaces 9 are formed in the coloring region, the capillary flow of the sample liquid in the chromatography strip 1 does not becomes uneven in the coloring region, and the detecting accuracy of the detected substance is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an immunoanalyzer using a chromatography strip. Specifically, a substrate is attached to a lower surface, and a chromatography strip is attached to a protective laminate on an upper surface. A space is provided on an upper surface and / or a lower surface of at least a part of a color forming region of the chromatography strip. Immune analyzer.

[0002]

2. Description of the Related Art As is well known, an immunoassay apparatus using a chromatography strip is provided so that an added test sample liquid can move in the chromatography strip by a capillary flow, and the sample is provided with a sample. A detection region for the substance to be detected is provided downstream of the liquid addition region. The detection area is provided so that if the substance to be detected is contained in the sample liquid that has reached the detection area, the detection area is colored or less colored. Alternatively, the amount can be detected or measured. Such an immune analyzer is disclosed in Japanese Patent Application Laid-Open No. 61-1454.
59, JP-A-64-32169, JP-A-1-11366
2, JP-A-1-244370, JP-A-1-63865 and JP-T-1-503174, etc., and these descriptions are also part of the description of this specification.

[0003] These immunological analyzers have a chromatography strip with a substrate on the lower surface and a protective laminate on the upper surface for protection of the chromatography strip and prevention of biohazard.

According to the study of the present inventors, it has been found that the capillary flow of the sample liquid is not uniform in a region where the analytical reagent is fixed, such as a coloring region of the chromatography strip. If the sample liquid flow is not uniform in the coloring region, the coloring in the coloring region is not uniform, and white spots and the like are generated in the coloring region, thereby lowering the detection accuracy.

As an attempt to make the capillary flow of a sample liquid in a chromatography strip uniform, a method in which both ends in the longitudinal direction of the chromatography strip are formed in a continuous tooth shape (unevenness) described in Japanese Patent Publication No. 2590055. It is known, however, that this does not attempt to equalize the flow in the colored area.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an immunoanalyzer using a chromatography strip, in which a capillary flow of a sample liquid in a coloring region is made uniform.

[0007]

Means for Solving the Problems In a chromatography strip having a substrate on the lower surface and a protective laminate on the upper surface, the present inventors provide a space in at least a part of the color-forming region, so that the capillary flow in the color-forming region can be improved. It has been found that white spots and the like derived from the non-uniformity of the sample are eliminated, and high detection accuracy can be obtained. That is, the present invention includes a chromatography strip in which a substrate is attached to a lower surface and a protective laminate is attached to an upper surface, and a space is provided in an upper surface and / or a lower surface of at least a part of a coloring region of the chromatography strip. Is an immune analyzer.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, the immunoassay apparatus of the present invention has a chromatography strip (2) attached to a lower surface and a protective laminate (3) attached to an upper surface. 1).

[0009] As the chromatography carrier of the chromatography strip, any of those known in the art can be used. For example, cellulose, nitrocellulose, cellulose acetate and the like are most often used.

[0010] The substrate or the protective laminate is applied to the chromatography strip by applying a glue (4) to the substrate or the protective laminate. As the paste, for example, a rubber-based, acrylic-based, or vinyl ether polymer-based adhesive is used.

When a carrier soluble in an organic solvent such as nitrocellulose is used as a chromatography carrier, nitrocellulose is dissolved in an organic solvent such as acetone and formed of a film soluble in an organic solvent such as polyethylene terephthalate. By spreading this on a substrate having a membrane, the chromatography carrier and the substrate may be bonded together. In the present invention, such a case is also included in the gluing between the chromatography stop and the substrate.

The substrate and the protective laminate may be conventional ones conventionally used in immunoassays using chromatography strips. For example, polyethylene terephthalate, polypropylene, polyvinyl chloride and the like are used.

The chromatography strip has a sample application area (5). When a sample liquid that may contain a substance to be detected is added to the sample application area, the sample liquid moves downstream by capillary flow.

The chromatography strip further comprises:
There is a coloring area downstream of the sample addition area. The coloring region is a region that develops color during the analysis, and includes a detection region (6) for detecting a substance to be detected in the sample solution. further,
As a coloring area, a control area (7) may be provided as necessary.

The detection region is provided so that a tracer composed of a labeled antigen or antibody or the like is accumulated in accordance with the presence or absence or the amount of the substance to be detected in the sample liquid moved from the upstream by the capillary flow. . "Depending on the presence or absence or amount of the substance to be detected" indicates that the accumulation amount of the tracer increases in the case of the sandwich assay, and decreases in the case of the competitive assay. That is, in the detection region, the target substance is specifically (in this case, the tracer specifically binds to the target substance), or the target substance and the tracer compete with each other, and if necessary, via a certain kind of cross-linked product , The compound to be bound is fixed.

Here, the “crosslinked product” means a substance that specifically binds to both the compound fixed to the detection region and the substance to be detected. For example, anti-mouse IgG is used
It is conceivable that the antibody is immobilized and mouse IgG against the antigen to be detected is used as the crosslinked product. In addition, it is also possible to use a complex of a compound that specifically binds to the compound fixed to the detection region and a substance that specifically binds to the substance to be detected as a crosslinked body. in this case,
The substance that specifically binds to the target substance is, for example, an antibody when the target substance is an antigen, or an antigen when the target substance is an antibody, and the compound fixed to the detection region and the compound fixed to the detection region. Examples of the combination of compounds that specifically bind to the compound include, for example, if one is bition, the other is an anti-bition antibody or avidin, and if one is sugar, the other is a sugar-binding protein. is there.

When the substance to be detected and the tracer compete with each other and bind to the compound fixed to the detection area, a second detection area for capturing the tracer not captured in the detection area may be provided downstream of the detection area. is there. This second detection area is also included in the “detection area” in the present invention.

As the label, a metal colloid such as an enzyme or a gold colloid, a non-metal colloid such as a selenium colloid, a colored resin fine particle, a colored liposome, and a dyed fine particle such as a dye fine particle are used. Therefore, the tracer is accumulated or not accumulated in the detection region, the chromaticity of the detection region is changed, and the presence or absence or amount of the substance to be detected in the sample liquid can be known by visually observing or measuring the chromaticity. .

The control area is an area for knowing that the sample liquid has passed through the detection area, and is provided so that when the sample liquid reaches the control area, the control area is colored if necessary. Therefore, the control region is provided downstream of the detection region if necessary. In order to cause the sample liquid to develop color when it reaches the control region, as is well known, the sample liquid contains, for example, one of a pH indicator, an enzyme or a tracer for controlling the color reaction, and the like. The control region may be immobilized with a compound that develops color when it reaches the control region.

The tracer may be included in a specific region (labeled region (8)) of the chromatography strip in advance, or may be added together with the sample liquid when the sample is added.

The "upper surface" refers to the surface of the chromatography strip on which the protective laminate is attached, and the "lower surface" refers to the surface of the chromatography strip to which the substrate is attached.

"Space" (9) refers to a portion where the protective laminate or the substrate is not glued to the surface of the chromatography strip.

According to the present invention, the capillary flow of the sample liquid is not disturbed only by providing a space in a part of the color forming region, and it is sufficient to provide a space in at least a part of the color forming region. . However, if a part of the coloring area is extremely small, the effect is of course ineffective. If a part of the coloring area is too small, it is difficult to avoid gluing.

Even if the space is the whole of the coloring area,
There is no problem even if it extends to the entire coloring area and the area before and after it. In addition, the effect may be greater and the gluing is easy. Is provided. The front and rear regions may be of any size as long as they are not all of the chromatography strip.

The space may be provided on the lower or upper surface of the chromatography strip, or on both the upper and lower surfaces.

The space can be provided by not gluing at least a part of the coloring area and the surface of the protective laminate and / or the substrate facing the area (FIG. 1,
(Fig. 2). In order not to glue the protective laminate and / or the substrate to at least a part of the color forming region, no glue is applied to the unglueed portion of the protective laminate, or if glue is applied, the adhesive strength of the glue is lost. The agent to be glued may be applied to the portion not glued. As the agent for losing the adhesive strength of the paste, all known agents can be used.

Alternatively, a thin film (10) may be placed between the chromatography strip and the protective laminate and / or substrate to avoid gluing (FIG. 3). If the film is placed between the protective laminate and the chromatography strip, it must be transparent.

The thin film may be any film as long as it does not absorb water.

As another method for providing a space, there is a method in which the surface portion of the protective laminate and / or the substrate facing at least a part of the color forming region is concave (11) (FIG. 4). To make it concave, two protective laminates or substrates are stuck together, and only the concave part is made into one sheet.
Easy.

The space can also be provided by gluing the protective laminate with two or more discontinuous portions of the chromatography strip except for at least a part of the coloring region (FIG. 5).

The space can also be provided by preventing the protective laminate or the substrate from covering at least a part of the color developing region (FIG. 6).

When the space is provided on both the upper surface and the lower surface of the chromatography strip, the method of not gluing may be the same method on the upper surface and the lower surface, or may be different. However, not covering both the protective laminate and the substrate is not desirable because it causes breakage such as bending of the chromatography strip.

Hereinafter, the present invention will be further described with reference to examples.

[0034]

EXAMPLE A 0.5 cm × 4.0 cm nitrocellulose membrane (Millipore, USA) was used as a substrate (pack laminate).
Affixed above. With the long side of the nitrocellulose membrane as a vertical, a solution containing the antigen from the syphilis protozoa was dropped linearly at about 1 cm from the lower end, then dried sufficiently to fix the syphilis antigen, and placed on the nitrocellulose membrane. A detection area was provided. Further, avidin was immobilized on the nitrocellulose membrane about 1 cm from the detection area on the upper side in the same manner as the syphilis antigen, and a control area was provided. After impregnating a glass fiber membrane (manufactured by Lydall, USA) with a labeled antigen obtained by labeling an antigen derived from syphilis with a selenium colloid, and a biotinylated selenium colloid obtained by binding biotin to the selenium colloid, The glass fiber membrane was dried to form a labeled area. This labeling area was affixed on the substrate so as to be slightly in contact with the lower end of the nitrocellulose film on the substrate obtained earlier. further,
0.5 × 1.0 as a sample addition area at the lower end of the label area
cm nonwoven fabric (manufactured by DuPont, USA) was adhered on the substrate so as to be in contact with the marked area.

A protective laminate (manufactured by Lintec Corporation) is adhered to the upper surface of the thus obtained chromatography strip, and syphilis antibodies in the specimen are detected using the obtained chromatography strip device. 50 μl of the serum sample is added to the sample addition area of the chromatography strip device, and 15 minutes after the addition of the serum, the determination is made by visually reading “redness” derived from the selenium colloid in the detection area and the control area.

In the determination of the results, those showing red in both the detection region and the control region are positive for syphilis antibody, and those showing red only in the control region are negative for syphilis antibody. If the control area does not show red, it is invalid.

In applying the protective laminate to the chromatography strip device, the following method was used so that the chromatography strip and the protective laminate did not adhere to each other in the detection area and the control area on the chromatography strip.

(1) Ink (UV curable ink) having the property of curing the paste surface of the protective laminate by irradiation with ultraviolet light
(Manufactured by T & K TOKA), and a protective laminate treated with ultraviolet irradiation is used. By applying this protective laminate on a chromatography strip,
In the cured ink application area (detection area and control area)
The protective laminate did not adhere to the chromatography strip. The chromatography strip device obtained by this treatment is referred to as a UV treatment method.

(2) A protective laminate in which a paste is applied to a portion of the protective laminate other than the portion where the protective laminate is in contact with the detection area and the control area of the chromatography strip is adhered to the chromatography strip, whereby the protective laminate and the chromatography strip are combined. An unbonded portion was provided between them. The chromatography strip device obtained by this method is referred to as a partial coating method.

(3) The protective laminate was applied to portions other than the detection area and the control area of the chromatography strip so that the detection area and the control area did not have the protective laminate. The chromatography strip device obtained by this method is defined as an opening method.

(4) As a control, the protective laminate was attached to the chromatography strip so that there was no space between the protective laminate and the chromatography strip. The chromatography strip device obtained by this method is referred to as a conventional method.

Using the above four types of chromatography strip devices, syphilis antibodies in 32 samples were detected, and the appearance of color in the detection region, which is a color development region, and the control region was observed. Table 1 shows the number of chromatography strip devices in which white spots remained or uneven color was formed in these color forming regions.

[0043]

[Table 1]

[0044]

As described above, by providing a space in at least a part of the color forming region of the chromatography strip of the immunoassay apparatus, the capillary flow of the sample liquid in the chromatography strip is prevented in the color forming region. Without uniformity, the detection accuracy of the substance to be detected is greatly improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing one example of an immunological analyzer of the present invention.
A is a plan view of the gluing surface of the protective laminate, and B is a side view of the immunological analyzer.

FIG. 2 is a plan view of a glued surface of a protective laminate as an example of the immunological analyzer of the present invention.

FIG. 3 is a diagram showing an example of the immunological analyzer of the present invention.
A is a side view, and B is a plan view of the glued surface of the substrate.

FIG. 4 is a diagram showing an example of the immunological analyzer of the present invention.
A is a plan view of the gluing surface of the protective laminate, and B is a side view of the immunological analyzer.

FIG. 5 is a plan view of a glued surface of a protective laminate as an example of the immunological analyzer of the present invention.

FIG. 6 is a side view of an example of the immunological analyzer of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chromatography strip 2 Substrate 3 Protective laminate 4 Glue part 5 Sample addition area 6 Detection area 7 Control area 8 Labeling area 9 Space 10 Thin film 11 Concave part

Claims (8)

[Claims] 1. A chromatography strip having a substrate adhered to a lower surface and a protective laminate adhered to an upper surface, and a space is formed on an upper surface and / or a lower surface of at least a part of a color forming region of the chromatography strip. The provided immunoanalyzer. 2. The immunoassay apparatus according to claim 1, wherein the space is provided by not gluing the partial region and at least one surface of the protective laminate and the substrate facing the region. 3. The method according to claim 2, wherein the paste is not applied to at least one surface of the protective laminate and the substrate facing the partial region, whereby the partial region and the at least one surface are not glued. The immunoassay device according to claim 1. 4. A method in which at least one surface of the protective laminate and the substrate facing the partial region is applied with an agent for losing the adhesive ability of the adhesive, so that the partial region and the at least one surface are glued. The immunological analyzer according to claim 2, wherein the immunological analyzer is not performed. 5. The immunoassay apparatus according to claim 1, wherein the space is provided by making at least one surface of the protective laminate and the substrate facing the partial region concave. 6. The space is provided by placing a thin film between at least one surface of the protective laminate and the substrate facing the partial area and the partial area,
The immunological analyzer according to claim 1. 7. The space is provided by attaching the chromatography strip to at least one of the protective laminate and the substrate at two or more locations where the chromatography strip is not continuous except for the partial area. The immunoassay apparatus according to claim 1, wherein the immunoassay apparatus is used. 8. The immunoassay apparatus according to claim 1, wherein the space is provided by preventing the protective laminate or the substrate from covering the partial area.